Ms. Firestone extended Marxist theories of class oppression to offer a radical analysis of the oppression of women, arguing that sexual inequity springs from the onus of childbearing, which devolves on women by pure biological happenstance.

“Just as the end goal of socialist revolution was not only the elimination of the economic class privilege but of the economic class distinction itself,” Ms. Firestone wrote, “so the end goal of feminist revolution must be … not just the elimination of male privilege but of the sex distinction itself: genital differences between human beings would no longer matter culturally.”